Final answer:
The external focus to correct the problem of a flaring right elbow during the concentric phase of a biceps curl is to B) Keeping the shoulder stable
Step-by-step explanation:
The client should focus on keeping the shoulder stable to correct the problem of a flaring right elbow during the concentric phase of a biceps curl. Squeezing the biceps will not help in correcting the elbow flaring. Engaging the core and focusing on the breathing rhythm are important for overall stability and performance but may not directly address the specific issue of elbow flaring.
By keeping the shoulder stable, your client will promote better alignment and control of the elbow joint, reducing the tendency for it to flare outwards. This can be achieved by maintaining proper form and technique, ensuring that the shoulder remains fixed and does not move excessively during the exercise. So therefore the correct answer is B) Keeping the shoulder stable